Edexcel M2 — Question 1 5 marks

Exam BoardEdexcel
ModuleM2 (Mechanics 2)
Marks5
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Mark schemeDownload PDF ↗
TopicImpulse and momentum (advanced)
TypeImpulse from velocity change
DifficultyModerate -0.3 This is a straightforward application of the impulse-momentum theorem with vectors. Students must find the change in momentum (mass × change in velocity), then calculate the magnitude using Pythagoras. It requires only direct formula application with no problem-solving insight, making it slightly easier than average for M2.
Spec6.03a Linear momentum: p = mv6.03f Impulse-momentum: relation

  1. An ice hockey puck of mass 0.5 kg is moving with velocity \(( 5 \mathbf { i } - 8 \mathbf { j } ) \mathrm { m } \mathrm { s } ^ { - 1 }\), where \(\mathbf { i }\) and \(\mathbf { j }\) are perpendicular horizontal unit vectors, when it is struck by a stick. After the impact, the puck travels with velocity \(( 13 \mathbf { i } + 7 \mathbf { j } ) \mathrm { m } \mathrm { s } ^ { - 1 }\).
Find the magnitude of the impulse exerted by the stick on the puck.
(5 marks)

Question 1:
AnswerMarks Guidance
Answer/WorkingMarks Notes
\(\mathbf{I} = \Delta\text{mom.} = 0.5[(13\mathbf{i} + 7\mathbf{j}) - (5\mathbf{i} - 8\mathbf{j})]\)M1 A1
\(= 0.5(8\mathbf{i} + 15\mathbf{j})\)A1
mag. of \(\mathbf{I} = 0.5\sqrt{8^2 + 15^2} = 8.5\) NsM1 A1 (5)
## Question 1:

| Answer/Working | Marks | Notes |
|---|---|---|
| $\mathbf{I} = \Delta\text{mom.} = 0.5[(13\mathbf{i} + 7\mathbf{j}) - (5\mathbf{i} - 8\mathbf{j})]$ | M1 A1 | |
| $= 0.5(8\mathbf{i} + 15\mathbf{j})$ | A1 | |
| mag. of $\mathbf{I} = 0.5\sqrt{8^2 + 15^2} = 8.5$ Ns | M1 A1 | **(5)** |

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\begin{enumerate}
  \item An ice hockey puck of mass 0.5 kg is moving with velocity $( 5 \mathbf { i } - 8 \mathbf { j } ) \mathrm { m } \mathrm { s } ^ { - 1 }$, where $\mathbf { i }$ and $\mathbf { j }$ are perpendicular horizontal unit vectors, when it is struck by a stick. After the impact, the puck travels with velocity $( 13 \mathbf { i } + 7 \mathbf { j } ) \mathrm { m } \mathrm { s } ^ { - 1 }$.
\end{enumerate}

Find the magnitude of the impulse exerted by the stick on the puck.\\
(5 marks)\\

\hfill \mbox{\textit{Edexcel M2  Q1 [5]}}